My parents just gave me their 89 240DL sedan with 235k miles. They have had the car for 8 years, most reliable car they have ever owned. Anway, the car has a problem now. When the engine is put under heavy load, such as climbing a hill, or any attempted pass, the engine loses power. It "skips" it will lose a great deal of power all of a sudden. It is intermittent, it will come in and out of full power. Very annoying and pottentially unsafe. The engine has had regular maintnance, burns no oil, and when it is running good, seems relativly normal. Also, not sure if it is related, but sometimes when attempting to start the engine, it will take unusual amounts of turnover to start, sometimes it stalls immediatley after start. Any help you could give me in diagnosing this problem would be helpfull.

Thankyou in advance.